The audience rating of television broadcasting programs (hereinafter simply referred to as TV programs or programs), especially those regarding commercial broadcasting stations are of great interest to their sponsors which are companies or enterprises, and hence, it is desired to simply and correctly grasp which programs were viewed, with respect to as many viewers (households) as possible. At the same time, it is preferable to avoid bothering the viewers for that purpose.
Conventionally, a special device is used for collecting audience data of TV programs, as described in Japanese laid-open (KOKAI) application No. 63-37726. This device is connected to a TV set of a viewer who is a monitor, so as to automatically record his or her watching channels and their time data. Which channel is currently being watched is detected by a channel detector. This is realized by picking up a leak wave from the local oscillator of the TV set. The detected viewing channel data and viewing time data are recorded in the device. The recorded data are transferred via a telephone line to a collection center by polling from the center within a limited period of time at midnight.
Such prior art technique requires a hardware device dedicated for collecting audience data at each of the monitor households. In general, the more is the number of the monitors, the more the preciseness of the audience rating research is improved. However, it will cost a lot to deliver such special devices to a lot of households. Also, the communication fees for collecting data are not negligible (especially in long-distance calls).
Therefore, conventionally, the area in which audience data are to be collected is limited and the number of monitors is also limited, thus making it difficult to perform nationwide data collection.
In addition, for the nationwide data correction, TV programs even of the same channel may be different with each other depending upon the areas, and the contents of programs vary day by day even on the same channel in the same area. Thus, the viewed channel and time data collected from a given monitor are compared, at the collection center, with program table data of that date of the area where the monitor resides, so as to determine the viewed time of individual programs. This process has to be performed for all the monitors, which will cause a problem that the more the number of monitors is increased, the greater is the processing load at the collection center.
In recent years, personal computers have come into wide use even in general homes, rapidly expanding the use of the Internet. The Internet is a gigantic aggregation of computer networks which are interconnected in a world-wide scale. Its main functions include electronic mail, net news (electronic bulletin board or electronic conference), file transfer (FTP: File Transfer Protocol), world-wide web (WWW), etc. In particular, the WWW is a set of hyper text documents written in a language called HTML (Hyper Text Markup Language), which links various items of information, dispersedly existing on the Internet, with one another to be accessed. The hyper text documents are distributed by computers on the Internet, called a WWW servers. A user, at a client computer, can access documents on the Internet by using a browsing software, called WWW browser (also referred to as a web browser). The connection of the client computer with the Internet is performed through an organization, generally called a service provider, which provides a service to let people to use the private communication line owned by the provider. All the documents of WWW are assigned with unique addresses on the Internet, called URLs (Uniform Resource Locators).
Recently, TV sets with an internet connecting capability or computers with a TV viewing capability have become commercially available for family use.
In these situations, the present invention aims to provide method and device for collecting audience data on TV programs, without the need for hardware devices dedicated for collecting audience data.
Another object of the present invention is to provide method and device for collecting audience data on TV programs, capable of reducing the processing load at the data collection center, by correlating, on the viewer's side, individual programs with viewed channels and time information.